Adaptations for nutrition Flashcards
What are the two types of nutrition?
- autotrophic nutrition
- heterotrophic nutrition
Define autotrophic nutrition (what are they in normal terms?)
organisms that make their won food from the simple inorganic raw materials, carbon dioxide and water
Producers
What are the two types of autotrophic nutrition?
- photoautotrophic
- chemoautotrophic
briefly described what autotrophic nutrition is and what it’s described as
organisms which use light as an energy source and perform photosynthesis, they are usually green plants
Described as holophytic nutrition
how do autotrophic bacteria differ from plants?
as the hydrogen needed to reduce carbon dioxide comes from hydrogen sulphide, not water
briefly describe what chemoautotrophic nutrition is and give an example
organisms which use energy from chemical reactions, these organisms are all prokaryotes and perform chemosynthesis (less efficient)
nitrifying bacteria in nitrogen cycle
Define heterotrophic nutrition, what is this in simple terms, which organisms are included in this?
organisms that can;t make their own food and consume complex organic molecules produced by autotrophs
consumers
animals, fungi, some protoctista and some bacteria
what three types of nutrition are included in heterotrophic nutrition?
- sapotrophic nutrition
- parasitic nutrition
- holozoic nutrition
define sapotrophic nutrition and what its used by
- feed on decaying/dead matter and have no specialized digestive system, instead they secrete enzymes onto food material outside the body (extracellular digestion)
- used by all fungi and some bacteria
Define parasitic nutrition and give some examples of parasite’s adaptions
where do endoparasites live? exoparasites?
- obtain nutrition from a host organism which always suffer some harm and often death
- headlice, tapeworm, plasmodium (malaria)
- endo live in host body, exo live on its surface
Define holozoic nutrition and what its used by, and define detritivores
- food is processed inside body inside specialized digestive system where digestive material’s absorbed into body tissues
- used by most animals
- detritivores feed on dead and decaying material
what is the difference between saprotrophs and detritivores
Detritivores consume detritus directly by eating dead organic matter.
Saprotrophs feed on dead organic matter through extracellular digestion, breaking it down externally before absorbing nutrients.
define mutualism/symbiosis
close association between members of 2 different species, but in this case both derive benefit from the relationship
Amoeba is the unicellular organism we study, what nutrition does it use? how does it obtain nutrients?
Holozoic nutrition, large SA:VOL
- obtains nutrients by diffusion (facilitated diffusion or active transport across cell membrane)
- does so by engulfing food (larger molecules) by endocytosis, lysosomes fuse w/food vacuole and release digestive enzymes
What sort of gut does the hydro gave?
sac-like gut
what are the hydra’s two layers of cells and what do they do?
ectoderm and endoderm
endoderm cells secrete protease and lipase to digest prey extracellularly and products of digestion are absorbed
how does the hydra kill its prey?
stinging cells on their six tentacles to paralyse
give an example of an organism with a simple tube like gut
earthworm
define peristalsis
rhythmic wave of coordinated muscular contractions in the circular longitudinal muscle of the gut wall, passing food along in 1 direction only
what must polymers be converted to? why?
monomers so they can be rebuilt into molecules needed by body cells
define the gut
long, hollow muscular tube which allows movement of its contents in 1 direction only
what are the four functions of the gut? define them
- Ingestion, the intake of food through the buccal cavity (mouth)
- Digestion, the breakdown of large insoluble molecules into small soluble molecules (mechanical and chemical)
- Absorption, passage of molecules and ions through the gut wall into the blood
- Egestion, elimination of waste not made by the body and indigestible food
Define chemical and mechanical digestion
chemical: digestive enzymes, bile and stomach acid contribute to break down food
mechanical: cutting and crushing by teeth (increase surface area) and muscle contractions of gut wall
where do the four gut functions occur?
ingestion and mechanical digestion in the mouth
chemical digestion in the stomach
chemical and absorption in the small intestine
what is the gut wall composed of? Going from outer wall in
- Serosa
- Longitudinal muscles
- Circular muscle
- Submucosa
- Mucosa
what does the serosa layer do? and what is it made up of?
made up of tough connective tissue to protect the gut wall and reduces friction with other organs while gut moves when processing food
what does the two muscle layers do?
longitudinal and circular make coordinated waves of contractions: peristalsis
what does the submucosa layer do? and what is it made up of?
made up of connective tissue containing blood and lymph vessels to removed absorbed products of digestion and nerves coordinate peristalsis
what does the mucosa layer do?
inner most layer which lines the gut wall, its epithelium secretes mucus to lubricate and protect the mucosa
